the 1960s, the central thesis of the Dynamic Capabilities theory is that "... the real key to a company's success or even to its future development lies in its ability to find or create a competence that is truly distinctive". In this literature the term "competence" is used in both the sense of degree of performance in some capability and as a low-level, short-term capability. Competence in the latter sense echoes the concepts from Hamel and Prahalad, but may also be identified with Leonard's Enabling and Supplemental Capabilities as well as the short-term Core Capabilities of a firm. The term "capabilities" is also used somewhat interchangeably with "competencies". The competencies or low-level capabilities are regarded as assets or knowledge-resources of the enterprise, alongside physical assets and other resources that are difficult for competitor firms to acquire. In this sense Teece's Dynamic Capabilities Theory is a move back towards the Resource-Based View of the Firm, but with a broader notion of "Resources" that includes intangible knowledge-based and practice-based resources, not just tangible assets. In the Dynamic Capabilities Theory, "Resources" are firm-specific assets that are difficult for competitors to acquire or imitate, "Organizational Routines" (based on prior work of Nelson and Winter) or "Organizational Competences" are the low-level capabilities of the firm and "Core Competences" are taken from the Hamel and Prahalad concept. Citing Dorothy Leonard (or Leonard-Barton), Teece et al. define (higher-level) Dynamic Capabilities as the "ability to integrate, build and reconfigure" these tangible and intangible assets. "Dynamic Capabilities thus reflect an organizations ability to achieve new and innovative forms of competitive advantage given path dependencies and market positions." "Path dependencies" refers to the history of development of organizational knowledge embedded in its capabilities, routines and technological assets – echoing the concept from Leonard, but on a macro-scale and explaining why competitive advantage takes time and persistence to build. The incorporation of "Routines" and path-dependent development of firms in the theory establishes the link to evolutionary theories of management and (business) strategy. The Dynamic Capabilities Theory also refers to notions of coherence, congruence and complementary assets across the firms portfolio of assets, routines, competencies and capabilities. This has resonances with similar notions of coherence in System-of-Systems Engineering and in Enterprise Architecture. Teece et al. also discuss Technological Assets, Structural Assets and Reputational Assets – echoing the three recurrent categories of Distinctive Capability identified by John Kay – Innovation, Architecture and Reputation.